User's Manual

Remote Module Per-Carrier Derating
DCM000000104 Rev Q 4-3
4.4 Remote Module Per-Carrier Derating
All signals that fall within a given Pass-Band range will “share” power amongst them. A multiple
channel effect is intermodulation, signals produced from non-linear effects between the intended
channel signals. This intermodulation may cause interference to receiving equipment. In order to
minimize intermodulation signals, power de-rating must be applied. In the USA there are FCC
Intermodulation Specifications published in the EIA Standard PN2009. Further derating is also required
to maintain the integrity of complex digital communications signals. The table below gives the maximum
per channel output levels allowed as a function of the number of channels. Note that depending on the
actual input levels, the gain may need to be reduced to comply with the above regulations.
The figures shown are to the nearest dB.
Table 3 Per-Carrier Derating
iDEN / Cellular / Paging/GSM900/700PS
(effective IP3 = +38dBm)
1.9 GHz PCS/1.8GHz GSM
(effective IP3 = +36dBm)
Power per
Carrier per
Antenna
Port (dBm)
Total Power
per Antenna
Port (dBm)
Number of
Carriers
Power per
Carrier per
Antenna
Port (dBm)
Total Power
per Antenna
Port (dBm)
Number of
Carriers
FM Dig FM Dig Digital Digital Digital
1 +24 +17 +24 +17 1 +15 +15
2 +15 +15 +18 +18 2 +13 +16
3 +14 +13 +18 +18 3 +11 +16
4 +13 +11 +19 +17 4 +9 +15
5 +12 +9 +19 +16 5 +8 +15
6 +11 +8 +19 +16 6 +7 +15
7 +10 +7 +18 +15 7 +6 +14
8 +9 +6 +18 +15 8 +5 +14
9 +8 +5 +18 +15 9 +4 +14
10 +7 +4 +17 +14 10 +3 +13
15 +5 +2 +17 +14 15 +1 +13
20 +3 0 +16 +13 20 -1 +12
25 +2 -1 +16 +13 25 -2 +12
30 +1 -2 +15 +13 30 -3 +12
Note! The above levels are shown for both FM and Digital (CDMA, TDMA,
GSM, & iDEN) Signals for 700-900 MHz, and Digital only for 1.9 GHz
PCS/1.8 GHz GSM. Some combinations may require additional Derating.
Consult Powerwave Technologies Inc. for further information.